Suppose we are given a particular fixed-length hash function h : 256-bits→ 128-bits. How can we use h to compute a 128-bit strong collision-free hash of a 512-bit input block? We consider several possible ways to extend h to a hash function H : 512-bits→ 128-bits. In the following, we suppose that m is 512-bits long, and we write m = m1m2, where m1 and m2 are 256 bits each. Method 1 Define H(m)...

The Clifford tori in S3 constitute a one-parameter family of flat, twodimensional, constant mean curvature (CMC) submanifolds. This paper demonstrates that new, topologically non-trivial CMC surfaces resembling a pair of neighbouring Clifford tori connected at a sub-lattice consisting of at least two points by small catenoidal bridges can be constructed by perturbative PDE methods. That is, one...

This article presents a cognitive model that reconciles a surprising observation in the picture-word interference (PWI) paradigm with the general notion that PWI is a form of Stroop interference. Dell'Acqua, Job, Peressotti, and Pascali (2007) assessed PWI using a psychological refractory period (PRP) paradigm, and concluded that the locus of interference in PWI is during the perceptual encodin...

In reaction time (RT) tasks, responses are especially fast when participants can anticipate the onset of an imperative response signal. Although this RT facilitation is commonly attributed to temporal preparation, it is unclear whether this preparation shortens the duration of early or late processes. We used the effect propagation property of the psychological refractory period paradigm to loc...

We give an explicit evaluation, in terms of products of Jacobsthal numbers, of the Hankel determinants of order a power of two for the period-doubling sequence. We also explicitly give the eigenvalues and eigenvectors of the corresponding Hankel matrices.

The purpose of this paper was to provide insight into the nature of response selection by reviewing the literature on stimulus-response compatibility (SRC) effects and the psychological refractory period (PRP) effect individually and jointly. The empirical findings and theoretical explanations of SRC effects that have been studied within a single-task context suggest that there are two response...

The recent developments of side channel attacks have lead implementers to use more and more sophisticated countermeasures in critical operations such as modular exponentiation, or scalar multiplication in the elliptic curve setting. In this paper, we propose a new attack against a classical implementation of these operations that only requires two queries to the device. The complexity of this s...

In this paper we investigate the properties and linear stability of travelling premixed combustion waves and the formation of pulsating combustion waves in a model with two-step chain-branching reaction mechanism. These calculations are undertaken in the adiabatic limit, in one spatial dimension and for the case of arbitrary Lewis numbers for fuel and radicals. It is shown that the Lewis number...

The complexity of a signal can be measured by the Recurrence period density entropy (RPDE) from the reconstructed phase space. We have chosen a window based RPDE method for the classification of signals, as RPDE is an average entropic measure of the whole phase space. We have observed the changes in the complexity in cardiac signals of normal healthy person (NHP) and congestive heart failure pa...